The main purpose of this research is to establish unique aspects of the action of L-phenylalanine mustard (alkeran; melphalan; sarcolysin). To date, the in vivo alkylation kinetics are distinctive as compared to HN2, BCNU and cytoxan. Furthermore, the levels of alkylation observed are much higher than shown by the other agents. In addition, there seems to be little or no excision repair of the L-PAM induced adducts. These preliminary characterizations suggest that L-PAM action is in some way different than the rapid acting, rapidly excised agents such as HN2. We are now engaged in efforts to 1) characterize L-PAM-DNA adducts, 2) determine the extent of repair, 3) determine the extent of double strand breakage of DNA and 4) determine any localization patterns in chromatin and DNA.